People with historic drink-driving and other relatively minor offences should have their convictions wiped, United Future leader and Minister Peter Dunne says.
Mr Dunne will write to Justice Minister Amy Adams urging a review of the Clean Slate Act, arguing it is too rigid in practice.
The Internal Affairs Minister said the law was designed to allow minor convictions to be wiped from a person's record after seven years.
But he knew of cases where people with relatively minor convictions from more than 20 years ago and who had not offended again, still had a criminal record because they had received a custodial sentence, or licence cancellation was involved.
"They now find their long distant past catching up with them when it comes to police clearances for employment, which sends a pretty perverse signal about the benefits of turning one's life around after criminal offending," Mr Dunne said.
"I think the law needs to be reviewed, with a view to introducing a provision that where a person was given a minor custodial sentence, and has not re-offended for a minimum of 10 years, the Clean Slate should apply."
Mr Dunne said a similar provision should be introduced for drink-drive convictions, but only if the original offence did not involve injury or harm to any other person.
His support for a review follows the presentation to Parliament of a petition organised by Glen Eden resident Eric Knight, calling for the Clean Slate Act to apply to individuals sentenced to a custodial sentence of 12 months or less, once 20 years has passed.
The petition received more than 150 signatures, and was this month presented by Labour MP for Kelston Carmel Sepuloni.
Labour's Justice spokeswoman Jacinda Ardern, a member of the Justice and Electoral Committee, has said it is a good time to review how the law is working.